Process of distilling tar and apparatus therefor



Sept. 19, 1933. A vA H, RADASCH 1,927,298

PROCESS OF DISTILLING TAR AND APPARATUS THEREFOR ATTORNEYS Sept. 19, 1933. A. H. RADAscH 1,927,293

PROCESS 0F ISTILLING TAR AND APPARATUS THEREFOR 5 Sheets-Sheet 2 Filed Sept. 28, 1929 INVENTOR M A4 22M' Mbmwrlw ATTORN EYS sept.- 19, 1933. A, H, RAD`ASH 1,927,298

PROCESS OF DISTILLING TAR AND 'PPARATUS THEREFOR Filed Sept. 28, 1929 I 5 Sheets-Sheet 3 BY 7., 3m-,M JW

ATTORNEYS Sept. 19, 1933. A H, RADASCH 1,927,298

PROCESS OF DI`S'TILLIYNG TAR AND APPARATUS THEREFOR ATTORN EYS Sept. 19, 1933. I

A. H. RADASCH PROCESS OF DISTILLING TAR AND APPARATUS THEREFOR Filed Sept. 28, 1929 5 Sheets-Sheet 5 ATTORN EYS Patented Sept. 19, 1933 PnocEss oF ms'riumc. TAR AND -APPARATUS THEREFOR Arthur n. nedaseh, south orange, NQJ., as-

sig'nor to The Barrett Company, New York, N. Y., a corporation of New Jersey Application september 2s, 1929 Serial No. 395,893

1s claims. (ci. zoe- 30) This invention relates to improvements in the distillation of tar and includes improvements in the process and apparatus' therefor. More particularly the invention relates to a process in 5 which tar is distilled by highly heated foul fuel gases, such as coke oven gases andin which two separate and distinct pitch products are simultaneously produced and in which the hot gases and vapors from one of the tar distillations in which ahigh melting lpoint pitch is produced are employed for the distillation of additional tar to produce a pitch of lower melting point suitable for use on roads, etc.

The present invention provides an improved process in which tar is distilled by `bringing it into direct and intimate contact with highly heated gases such as coke oven gases with regulation of the process to produce a pitch of a high melting point, i. et about 350 o r 400 F. or higher, and hot enriched gases, and in which the hot enriched gases are employed for the distillation of additional tar by bringing the tar into direct and intimate contact therewith, and separately collecting all of theresidue from this second distillation to produce -a separate pitch product which may be a low melting point pitch.

The present invention also *providesl an im-` proved process in which thev hot enriched gases resulting from the two separate distillations in which separate quantities of tar are brought into direct contact with the hot gases in separate distilling operations, may be employed for preheat ing and distilling the tar to be employed in either or both of the distilling operations. The enriched gases will thus be cooled simultaneously with the preheating of the tar, with consequent condensation and separation of oils from the gases so cooled.

The process of the present invention is a combined process including two successive operations. The rst oi' these is carried' out by maintaining continuously changing portions of the tar, in the form of a ne intense spray, in direct contact with highly heated gases such as coke oven gases for a short time; rapid distillation is thereby eifected, any considerable conversion to coke being prevented by the short duration of the dis# tillation; the gases are enriched by the vapors produced by the distillation, and a distillation residue is produced in the form of a pitch of desired melting point which is readily controlled by regulating the duration of contact of the tar with the hot gases, the temperature of the gases, etc. The enriched gases leaving the zone of this rst distillation have been cooled by this distillation considerably below their initial temperature, but are still relatively hot, e. g. 350 C. or more.

This iirst distillation is supplemented by a fur'- ther distillation in which the hot enriched gases are employed as the heating medium by bringing them into direct contact with tar to effect distillation thereof, and the residue from this distillation is collected as a separate pitch product,` which is a pitch of lower melting point than that produced in the rst operation. Either or both of these disti1ling operations in which tar is brought into direct contact with hot gases can advantageously be supplemented by a preheating operation in which the tar for either of the distilling operations or the tar for both of the distilling operations is preheated by indirect contact with the hot enriched gases after they have left the stills where theyare employed for distillation by direct contact, or the hot enriched gases may be employed for a preliminary distillation by being brought into direct contact with the tar which is to be further distilled in the first distilling operation.

`When tar, which is subsequently to be distilled by being -brought into direct contact with hot gases in either of the distilling operations of this invention, is rst heated by indirect contact with the hot enriched gases, light oils may be distilled from the tar, and these light oils may be sepa- 8 ratelydrawn off and condensed to give a light oil distillate. The resulting preheated and` partly distilled` tar is then brought into direct contact with the hot gases to eil'ect further distillation 90 and the production of pitch. l

The word tarvas used'in this patent is u ndeistood to include raw tar, dehydrated tar, or partially distilled tar from which more or less of the more volatile components have been removed, e. g. semi-pitch. The apparatus of the present invention includes two stills. The first still is connected with a source of highly heated gases, such as coke oven gases, with means for supplying tar thereto and for removing high melting point pitch therefrom, and with means for bringing the tar intoV direct and intimate contact with the hot gasesl passing through the still in the form of a fine intense spray whereby the temperature of the m5 hot gases entering the still is quickly lowered and the tar is rapidly distilled and the resulting pitch and enriched gases are brought substantially into equilibrium in a relatively short time. vThe gases leave the still at a suciently high temperaturev to carry the vapors of the higher boiling constituents resulting from the production of the Vhigh melting point pitch as well as the lower boiling constituents.

From thisrst still the gases, cooled to a temperature at which tar can be distilled without extra precautions to prevent the formation of coke and enriched by distillate vapors from the rst distilling operation pass to a second still -where they are employed for the distillation of other tar and the production of a pitch of lower melting point and distillate oils. This second still is provided with means to collect the entire residue from the second distillation and draw it off into a separate pitch storage tank.

The gases'and vapors leaving the second still are passed to a condensing system and may advantageously be used for preheating and partly distilling the tar for either or both of the distilling operations above described. When the preheating and distillation is effected by indirect contact between the tar and the hot gases, the heat interchanger employed serves both for preheating the tar and for condensing oils from the gases and vapors. Two heat interchangers may be employed in series for separately preheating the tar for each of the distilling operations, or the tar for both distilling operations may be passed through the same heat interchanger.

When the tar is preheated by indirect contact with the hot gases and vapors, and the preheating is sulilcient to effect distillation, a vapor box or separating chamber for the vapors resulting from the preheating and distillation is advantageously provided, and a separate condenser for these vapors may be used to advantage so that a separate light distillate can be taken off and condensed before the preheated tar enters either of the stills. In this way a separate light oil fraction is produced and this oil fraction Imay be produced under vacuum, by providing a vacuum pump on the vapor chamber.V By iirst removing light oils from the tars by means of a vapor chamber and separate condensing system, the

distillate produced in the subsequent distillation by direct contact with the hot gases is a heavier distillate, free, or substantially so, from lower boiling constituents, and can, therefore, be condensed with less cooling of the admixed inert gases. l

The gases employed in the primary still for carrying out the primary distillation, are highly 'heated gases,` such as are available in large amounts and at high temperatures at various coal carbonization or distillation plants, such as coke oven plants, gas retort plants, producer gas plants, water gas plants, low temperature carbonization plants, etc. The gases from coke ovens, for example, leave the coke ovens at temperatures around 450 to 850 C. TheseV highlyA heated gases are at such a high temperature that if brought into contact with a limited amount of tar or pitch in an indiscriminate manner, coking of the tar or pitch would take place, since the gases are at a temperature considerably higher than that at which coking of pitch will occur; however, by bringing the tar or pitch into thorough and intimatecontact with the highly heated gasesv in the form of an intense and well distributed spray, and in a suihcientquantity, the gases will be rapidly cooled and a high melting point pitch will be produced together with a high yield of distillate oils and minimum decomposition of the tar constituents.

The gases and vapors leave the rst still at a` high temperature, for example, around 250 to 425 C; These hot enriched gases contain the higher boiling constituents distilled from the tar in the production of pitch of high melting point. These hot enriched gases have a considerable distillation' capacity for tar or preheated tar, and by bringing a regulated amount of tar into direct and intimate contact with the hot enriched gases, a considerable distillation of oils from the tar can be eiiected with resulting increase in the content of the enriched gases in vapors of lower boiling range.

Some of the heaviest constituents carried in the hot gases may be condensed during the second distilling operation, such as heavy resinous or semi-solid constituents, depending upon the temperature to which the hot enriched gases are cooled and on the concentration of them in the gases by direct contact with the tar in the second still. Such'heavy constituents as are separated out from the hot enriched gases will be drawn off with the pitch produced during the second distilling operation. The pitch produced in the second still is a pitch of lower melting point. The hot enriched gases leave the second still at a lower temperature and ordinarily with an increased percentage of oil vapors, although the vapor content as expressed in volume percent, may remain unchanged or be reduced by condensing from the gases vapors of higher boiling range equal to or greater in amount than the vapors of lower boiling range added to the gases during the distillation in the second still.

The hot enriched gases coming from the second still may be passed directly to condensers which may include one or more heat interchangers, vapor boxes and condensers, for preheating and partially distilling the tar to be fed to either or both stills, or the tar to be distilled in the first still may be subjected to a partial and preliminary distillation by direct contact with the hot enriched gases before these gases enter the rst condenser.

By countercurrent flow of the tar and the hot enriched gases in a heat interchanger, the tar can be preheated to a temperature approaching that of the hot entering gases and the gases can be cooled to a temperature approching that of the cold enteringtar. Such preheating of the tar is often advantageous since it enables the tar to be brought into direct contact with the enriched gases in a preheated condition and thus increases distillation capacity. The preheating may be car ried to such a temperature that a low boiling oil can be separately removed in a suitable vapor box before the preheated residue is brought into direct contact with the hot mixed gases.

Tar of the same composition may be distilled in each of the stills of the present invention, or tars of different compositions may be distilled in each still. The tar distilled may be coke oven tar, gas retort tar, water-gas tar, producer gas tar, etc., or heavier or lighter tar, or tarry oil, or partly distilled tar, etc.

The invention is particularly valuable for the distillation of coal tar at by-product coke oven plants where a large volume of high temperature gases are available containing a large amount of useful heat, which is commonly dissipated and lost. By the practice of the present invention at a by-product coke oven plant, a high melting point pitch with a melting point of around 350 or 400 F. or higher is readily produced simultaneously with a pitch of lower melting point, suitable, for

riched gases from the irst still in which the high melting point pitch is made for carrying out the second distillation in which the lower melting point pitch is produced. Various oil fractions may be simultaneously produced, such as creosote oil, v a tar acid or carbolic oil, etc.

It will thus be seen that the present invention provides for the simultaneous production of two separate pitches, one of which is a higher melting point pitch and the other of which is a lower melting point pitch, with utilization of the heat contained in the hot enriched gases resulting from the ilrst distillation for distilling the tar in the second distillation. It will further be seen that oils of various kinds can be produced from the distillation operations by cooling the enriched gases resulting from the distillation in the first and second stills, and where the hot enriched gases from the' second still are employed vfor pre- '1 heating the tar by indirect contact therewith, a part of the distillate oils may be removed in a vapor box and then condensed as a separate oil product. In all cases the hot enriched gases resulting from the high temperature distillation are employed for further distillation by direct contact with tar and the pitch residues from the first and second distillations are collected separately as distinct products', or part or all of the pitches may be blended to form a blended product.

The invention will be further described in connection with the accompanying drawings, vsome of which are more. or less diagrammatic, illustrating different modified forms of apparatus which are comprised by this invention, but it is intended and will be understood that the invention is illustrated thereby and is not limited thereto. The

drawings show one adaptation of the invention in more or less detail as applied more particularly to a coke oven plant with utilization of the hot coke oven gases for the distillation of tar according to the invention.

Fig. 1` is a plan view of one adaptation of the xinvention showing in more or less detail its application to a coke oven plant;

Fig. 2 shows an elevation of Fig.l 1;

Fig. 3 is a cross-section through the still of Fig. 1;

Fig. 4 shows schematically the apparatus shown in greater detail in Figs. 1-3; and

Figs. 5-12 show schematically tions of the invention.

In the drawings, 5 indicates a coke oven battery, the ovens of which are connected in the usual way with uptake pipes 6 which connect with a collector main 7. Y A cross-over main connects the collector main with condensers, etc., Jnot shown/ Gas'collecting means, shown schematically, may be of the usual type. At the opposite side of the oven block to the usual uptake pipes the distillaother adaptation apparatus of this invention is located. Two

stills 10 and 11 are shown. Selected ovens of the battery are connected through uptake pipes 12 with a hot gas header 13 which conveys the gases from the uptake, pipes 12 into the still4 10. The uptake pipes 12, the hot gas header 13 and the stills 10 and l1 are insulated as indicatedV at 14.. By the proper manipulation of valves in the uptake pipes 12 and the uptake pipes 6, the gases from the selected ovens maybe directed either to the cross-over main 7 or to the stills 10 vand 11 where they are used for the distillation of tars.

' The hot coke ovengases enter the still l0 at a high temperature. The tar is sprayed into the the tar into the hot gases, the' tar is distilled and the gases are enriched in oil vapors. The fresh tar comes into direct contact with the hottest gases, and the pitch leaves the still in contact with partially cooled and partially enriched gases. By this concurrent iiow oi the tar and gases through the still, a pitch of high melting point is formed without undesirable over-distillation and/or formation of excessive coke in the still. The tar enters the still through the pipe 17 and the pitch is withdrawn through the trap 18 and the levelling arm 19. A'The depth of liquid maintained in the main is controlled by the position of the levelling arm 19. vThe pitch produced is drawn'oif into the trough 20 in which a constant stream of cold water 21 is maintained, and on meeting this cold water the pitch is chilled and granulated in solid granules.l The granulated pitch is collected in any suitable storage bin 22.

The hot enriched gases leaving the still l0 pass up through the still 1l where they are sprayed with other tar from the nozzle or nozzles 25. The tar is sprayed on to the battles 26. This causes a large surface of the tar to be exposed to the action of the hot gases and results in distillation of the tar and aids in removing from the gases any particles of spray which may be carried from the still l0. The spray within. the still 10 is so intense that the gases leaving the still are substantially detarred except for drops of thel spray which may be carried from the still by thel distillation in the still 11 is drawn oif through the' line 23 to the tar storage tank.29.

The hot enriched gases'leaving the still 11 are passed to suitable condensing means for the removal of the oil vapors-carried by the gases.

Higher boiling constituents, such as resinous and semi-solid materials, distilled from the tar in the,

still 10, where a high melting point pitch is producedfrom the tar, may be condensed in the still 1l as a result of the cooling caused by contact with the tar and distillation of the tar from the nozzle 25. Any condensate producedv within the still-11 by cooling and condensing of vapors carried over from the still 10 will be added to the residue of the distillation within the still 11 and will be drawn off into the pitch receiver 29. The pitch collected in 29 is a lower melting point pitch than that obtained in 22.

The heat in the gases leaving the still 11 may be utilized for preheatingA tar, which may be either the tar supplied to the stillA 10 through the line 17, or the tar sprayed into the gases in the still 11 from the nozzle 25, or both tars may be heated simultaneously or sepaartely by indirect contact with the hot enriched gases.

According to the arrangement in Figs. 1-3, tar is supplied to both stills from the line 30. A part goes directly tothe stillln through the line 17 and the balance goes through the line 31 to the `heat interchanger 32, and thence to the nozzle 25. The hot gases from the still 11 pass through\ the main 33 into the lowerpart of the heat interchanger and pass upI through the heat interatv changer and out through the main 34 into the fractional condenser 35.

The tar in passing through the heat intery changer in indirect contact with the hot enriched gases is preheated and the gases are cooled and heavy oils separate from the gases. These heavy oils are drawn oil through the line 36 and mayl be separately collected as a heavy oil product or may be blended with other oil fractions to produce a blended oil product.

'Ihe partially cooled gases leaving the heat interchanger are fractionally cooled in the condenser 35 to yield several oil fractions. These oil fractions may be separately collected or they may be blended to form larger fractions. The entire clean oil condensate may be collected with advantage as two separate fractions constituting a creosote oil fraction of higher boiling range and a tar acid or carbolic oil fraction of lower boiling range. The creosote oil fraction may be collected in the tank 38 and the carbolic oil fraction may be collected in the tank 39.

The heat interchanger shown comprises three sections for the separate collection of three fractions of condensate through the lines 40, 41 and 42, respectively. The sections ofthe condenser are connected with the headers 43 and 44 and so that fractions may be drawn olf into the creosote oil storage tank or the carbolic oil storage tank as desired.- The cooling medium, e. g. water, enters the condenser 35 at 45 and passes up through the column in a direction countercurrent to the flow of the gases.

The hot enriched gases pass down through the condenser 35` and the cooling medium enters at 45 through the bottom of the tower and passes up through the tower through the coil 46 in a direction countercurrent to the flow of the hot gases. The tower is divided into three sections by the partitions 47 and 48. There is an opening 49 in each partition to allow the hot gases to flow through the condenser, and around each opening is a collar 50 to prevent the flow of the condensate from one section to the section immediately below it. The draw-offs for the condensate 40 or 41 are positioned near the partitions 47 and 48 respectively, so that the liquid does not collect on either partition to a height above the height of the collar 50. Batlle 51 is provided over each of the openings to prevent condensate dripping from the coil above, down through either opening into a lower section of the tower.

Cold water may be used as the cooling medium. The water enters at 45 and in passing up through the coil through the tower is heated, and the water leaving at 52 is at an elevated temperature. In the lower part of each of the upper sections or in the upper part of each of the lower sections pipes 53 and 54 branch off of the coil 46. Warm water may be drained from the coil through either or both of these branch pipes or cold water may be admitted at either or both of the branch pipes to regulate the amount of cooling effected in each section of the condenser.

Beyond the condenser an exhauster 55 is situated and means for the recovery of ammonia and light oils are located beyond this exhauster.

The arrangement here described may be employed for distilling raw coke oven tar to produce pitch with a melting point of 400 F. in the first distillation operation and a lower melting point pitch suitable as a base for road tar may be produced simultaneously in the second distilling operation. The temperatures of the gases, etc. at different coke oven plants vary, and the tlgures here given are merely illustrative and are not to be considered in a limiting sense. operation may be so controlled as to distill off approximately 15% of oils in the still 11 to produce a road base with a viscosity of 55 to 175 seconds Engler (100 cc. at 100 C.) and a specific gravity of 1.16 to 1.22 at 25. C. This road tar base may then be blended with tar in suitable proportions to produce road tar.

The gases entering the still 10 are sprayed with an intense spray of the raw tarl supplied through the line 30 and the line 17 to the still. The tar is distilled to 400 F. melting point pitch which is drawn off into the storage bin 22. The hot enriched gases leave the still 10 and enter the still 11 at a temperature between 320 and 400 C., and in passing up through thev still 11 are sprayed with additional tar supplied through the line 30 preheated in the heat interchanger 32. This tar is distilled to pitch of a melting point suitable for road tar base. .The gases are further enriched in the still 11 and leave Athe still at a temperature in the neighborhood of, for example, 20D-250 C. and pass to the'heat interchanger. The tar enters the heat interchanger through the line 3l at a temperature in the neighborhood of 50 C. -Within the heat interchanger it isheated and the enriched gases from the still 11 are simultaneously cooled. Heavy oil is drawn off from the heat interchanger and the gases given ofi from the heat interchanger are fractionally cooled to produce the desired fractions. Fractionation isadvantageously so carried out that oreosote oil and carbolicroil fractions are obtained, and these are collected in the tanks 38 and 39 respectively. y

Various types of condensers may be employed for recovering the oils from the gases leaving the second still. Indirect or direct condensers may be employed. The arrangement here shown in detail may be used to advantage, although other means for cooling A.the gases to recover one or more oil fractions and for simultaneously heating a part or all of the tar as desired may be employed.

Fig. 4 shows schematically the apparatus and process described more in detail in connection with Figs. l to 3.l The condensing means employed beyond the heat interchanger is omitted. The still Si corresponds with the still 10. The still S2 corresponds with the still 1l. I is the heat interchanger 35. The tar enters the heat interchanger as indicated by the arrow and legend which correspond with the position 3l of Figs. 1 to 3. The tar entering at 17 -of Figs. 1 to 3 is indicated by the arrow and legend in connection with S1. The pitch draw-ofi" 19 is indicated by the legend pitch. As Fig. 4 corresponds to Figs. 1 to 3, Figs. 5 to 10 show schematically other processes and arrangements of apparatus within the scope of the invention.

Whereas according to Fig. 4 the tar to be distilled in S2 is preheated in I, in Fig. 5 the tar to be distilled in S1 is preheated in I. This increases the capacity of the apparatus for high melting point pitch, and -where the quantity of high melting point "pitch produced is increased,

The

the quantity of lower melting point pitch prov separate heating coils may be arrangedv in parallel in I for the preheating of the tars, or the heating coils may be arranged in tandem in which case the tar for either Si or Sz will be brought into indirect contact with the-hotter gases and the other tar will be brought into contact with gases which have already been partially cooled by the previous preheating of tar.

Although the tar may be preheated by indirect contact with the enriched gases as described in connection with` Figs. 4 to 6, it may also be preheated in other ways, or the tar may be employed without preheating. 'I'he tar used in Sz is preferably preheated inorder not to cool the gases in S2 to too low a temperature, although cold tar may be employed in small amounts in Sz for distillation. Fig. 7 shows the arrangement of stills S1 and Sa without any preheater and shows one means of supplying the tars to the stills and drawing oil the pitch products.

. Fig. B is a somewhat similar arrangement, but in addition means is provided for partially distilling the tar to be employed in Si by bringing `it into direct contact with the hotenriched gases leaving the still S2 in passing up through the still S3. Residue from the distillation in S3 is drawn oil' and supplied to the still S1.

Figs. 9 and l0 show modifications of the arrangements shown in Figs. 4 and 5 respectively, in which the tar after being preheated in I is passed to a vapor box V before being brought into direct contact with the hot gases. In I the tar is preheated above the boiling point of lower boiling constituents of the tar. When the tar is released in the vapor box V these lower boiling constituents volatilize andY separate from the nonvolatilized residue. The vapors pass to the condenser C where a separate low boiling distillate is condensed, and this may be separately collected. In the arrangement shown in Fig. 9 the residue from V is further distilled in S2. Fig. l0 shows a similar arrangement whereby the residue from V is distilled in S1.

Figs. l1 and l2 are still further modifications corresponding to Figs. 9 and l0, except that in each case a vacuum pump P is shown for maintaining the vapor box under a vacuum. In this manner ahigher fraction of distillate may be obtained from C with the same temperature of preheat. 'Ihe showing is schematic and it is to be understood that proper means for the removal of the residue from the vapor box through a suitable pump or barometric column is to be provided.

In each of the arrangements herein described as comprised by the invention, separate distillatins of the tars are eifected. The enriched gases from the rst distillation pass from the still S1 into the still S: and in this second still the enriched gases are employed for distillation of additional tar.' Theresidue from this second distillation is all drawn olf as a separate pitch product. The hot enriched gases from the second p distillation may be employed for preheating, and

where desired for distilling either of the tars by direct or indirect contact before these tars.

are subjected to distillation inthe stills Si and Sz respectively. The oils are recovered from the hot enriched gases by suitable condensing means as by indirect contact with tar to be preheated or direct or indirect contact with water or ammonialiquor. Although the vinvention has been described more particularly as applied to the distillation of raw coke oven tar with hot coke oven gases. other tars ormixtures of tars may-be distilled, including gas house tar, water gas tar, producer gas tar, etc., and the hot gas from gas retorts, water gas machines, gas producers, etc. may be employed for the distillation, the figures given herein being modified as necessary to apply to such variations.

References to pitch melting points refer to melting points determined by the method described in Methods of Analysis Used in the Coal Tar Industry, by J. M. Weiss, in the Journal of Industrial and Engineering Chemistry, volume 10, No. 10, October 1918, page 81'7. Creosote oil boiling points refer to boiling points determined by Method D-246-30 of the American Society for testing materials.

I claim:

l. The method of producing two separate pitch products and distillate oil by successively distilling two separate tars by direct and intimate contact with highly heated gases, which comprises bringing one tar into direct and intimate contact with the highly heated gases in the form of a ne intense spray thereby distilling this tar and producing a pitch of high melting point and hot enriched gases containing the oil vapors from such distillation, passing the hot enriched gases into direct contact with the additional tar to eiect distillation of such other tar, and separately collecting all the residue from such distillation as a separate pitch which has a lower melting point, and cooling the resulting gases and vapors to condense oils therefrom.

2. The method of distilling tar and producing distillate oil which comprises bringing tar into direct and intimate contact with highly heated gases in the form of a ne intense spray, thereby distilling the` tar 'and producing a pitch of high melting point and hot enriched gases, bringing the hot enriched gases into direct and intimate contact with additional tar thereby distilling this tar and producing pitch of lower melting point and enriching the gases in vapors of constituents volatilized from this tar and bringing the resulting gases into direct heat interchanging relation with one of the tars whereby the tar is preheated and oils are condensed from the gases.

3. The method of distilling tar and producing distillate oil therefrom which comprises bringing tar in a still into direct and intimate contact with highly heated gases in the form of a fine intense spray, thereby distilling the tar and producing a pitch of high melting point and hot enriched gases, bringing the hot enriched gases into direct and intimate contact with additional tar thereby producing a pitch of lower melting point and enriching the gases in vapors of constituents volatilized from this tar, bringing the tar to be fed into the first mentioned stll into direct contact with the resulting gases and vapors before feeding the tar to said still and cooling the resulting gases and vapors to condense oils therefrom.

4. The method of distilling tar and producing distillate oil therefrom which comprises bringing tar intO direct and intimate Contact With highly s heated gases in the form of a fine intense spray, thereby distilling the tar and producing a pitch of high melting point and hot enriched gases. bringing the hot enriched gases into direct and intimate contact with additional tar thereby propreheated and oils are condensed from the gases,

passing the preheated tar to a vapor box and ashing it therein, separately collecting the vapors flashed from the preheated tar and condensing them, and distilling the residue by 'direct contact with the hot gases.

5. The method of distilling tar and producing distillate oil therefrom which comprises bringing tar into direct .and intimate contact with highly heated gases in the form of a fine intense spray, thereby distilling the'tar and producing a pitch of high melting point and hot enriched gases, bringing the hot enriched gases into direct and intimate contact With additional tar thereby producing apitch of lower melting point and enriching-the gases in vapors of constituents volatilized from this tar, passing the resulting gases into indirect heat interchanging relation With tar to be distilled whereby the tar is preheated and oils are condensed from the gases, passing the preheated tar to a vapor box, maintaining a vacuum on the vapor box whereby lower boiling oils are distilled from the heated tar, condensing the lower boiling oils and recovering a separate oil product, and distilling the residue by direct contact with the hot gases.

6. The method -of distilling tar by direct and intimate contact with hot coal distillation gases and recovering distillate oil therefrom which comprises bringing tar into direct and intimate contact with the hot gases in the form of a fine intense spray, whereby the tar is distilled to pitch of high melting point and the gases are substantially detarred and are enriched in -oil vapors, separately collecting the residue from this distillation as a pitch product, bringing additional tar into direct contact with the enriched gases whereby said tar is distilled to pitch of lower melting point, separately collecting the residue from this distillation as a separate pitch product, and then cooling the resulting gases to separate oils therefrom.

7. The method of distilling tar with hot coke oven gases and producing oil and pitch therefrom Awhich comprises bringing tar into direct and intimate contact with hot coke oven gases in the form of an intense spray while the gases are vat a temperature approaching that at which they leave the ovens, thereby distilling the tar to pitch with a melting point of at least 350 F. and substantially detarring the gases and enriching them in oil vapors, passing the gases enriched in oil vapors into direct contact with additional tar whereby it is distilled to pitch, separately collecting this pitch as a separate pitch product, and bringing said additional tar into indirect heat interchanging relation with the resulting enriched gases before said distillation to preheat the tar and simultaneously cool the gases and separate oils therefrom.

8. The method of simultaneously and continuously producing oils, pitch with a melting point of 350 F. or over, and a road tar base by distilling coke oven tar in hot coal distillation gases, which comprises spraying a portion of the tar in the form of a fine intense spray into direct and intimate contact with the hot coal distillation gases, whereby the tar is distilled and the gases are substantially detarred and are enriched in oil vapors, and regulating the distillation to produce pitch with a melting point of at least 350 F., bringing the remainder of the tar into direct contact with the resulting enriched gases in an amount such that this remainder of the tar is distilled to pitch suitable for .Toad tar base, separately collecting the product of this distillation for road tar base and bringing the resulting gases enriched in oil vapors in indirect contact with said remainder of thetar before spraying it into the enriched gases, whereby the remainder of the tai' is preheated and the gases are cooled and heavy oils4 areseparated therefrom, and then further cooling the gases to condense lighter oils therefrom, and separately co1- lecting the heavier and lighter oils to form creosote oil and carbolic oil fractions.

9. Apparatus for distilling tar comprising a still having means for introducing highly heated gases thereto and for removing hot enriched gases therefrom, and having means for introducing tar thereto and for producing and for withdrawing pitch therefrom, and having means for bringing the tar into intimate contact with the gases in the still in the form of a ne intense spray to effect rapid distillation and the production of pitch and hot enriched gases, a second still provided with means vfor introducing tar thereto and for introducing the hot enriched gases thereto and for bringing the tar and hot enriched gases into direct contact and having means for thecollection and withdrawal of the residue from the distillation resulting from the direct contact of the tar and hot enriched gases and for the removal'of the resulting enriched gases therefrom, and means for bringing the hot enriched gases and the tar fed to one of the stills into indirect heat interchanging relation before being fed to the still.

10. Apparatus for distilling tar comprising a still having means for introducing highly heated gases thereto and for removing hot enriched gases therefrom, and having means for introducing tar thereto and for producing and for withdrawing pitch therefrom, and having means for bringing the tar into intimate contact with the gases in the still in the form of a fine intense spray to effect rapid distillation and the production of pitch and hot enriched gases, a second still provided with means for introducing tar thereto and for introducing the hot enriched gases thereto, and means for bringing the tar and hot enriched gases into direct contact to distill the tar to pitch of a low melting point and to enrich the gases, means for withdrawing the pitch and the hot enriched gases and means for using the hot enriched gases to preheat and distill one f said tars before use for said distillation.

11. Apparatus for distilling tar comprising a still having means for introducing highly heated 1 gases thereto and for removing hot enriched gases therefrom, and having means for introducing tar thereto and for producing and for withdrawing pitch therefrom, and having means for bringing the tar into intimate contact with the gases in the still in the form of a ne intense spray to eilect rapid distillation and the production of pitch and hot enriched gases, a second still provided with means for introducing tar thereto and for introducing the hot enriched gases thereto, and means for bringing the tar and hot enriched gases into direct contact to distill the tar to pitch of a low melting point and to enrich the gases, means for withdrawing the pitch and the hot enriched gases and means for bringing the tar to be fed to the first mentioned still into direct contact with the resulting enriched gases before being fed to said still.

12. Apparatus for distilling tar comprising a still having means for introducing highly heated gases thereto and for removing hot enriched gases therefrom, and having means for introducing tar thereto and` for producing and forwithdrawing pitch therefrom, and having means for bringing the tar into intimate contact with the gases in the still in the form of a fine intense spray to effect rapid distillation and the production of pitch and hot enriched gases, a second still provided with means for introducing tar thereto and for introducing the hot enriched gases thereto, means for bringing, the tar and hot enriched gases into direct contact to distill the tar and produce pitch of a low melting point and enriched gases, means for withdrawing the pitch, a heat interchanger, means for passing the enriched gases from the second still through the heat interchanger and for bringing them into indirect contact with one of the tars therein whereby the tar is preheated and the enriched gases are cooled, a vapor boi? gases thereto and for removing hot enriched,

gases therefrom, and having means for introducing tar thereto and for producing and for withdrawing pitch therefrom, and having means for bringing the. tar into intimate contact with the gases in the still in the form of a ne intense spray'to effect rapid distillation and theV production of pitch and hot enriched gases, a second still provided with means for introducing tar thereto and for introducing the hot enriched gases thereto, means for bringing the tar and hot enriched gases into direct contact to distill the tar and produce pitch of a low melting point and enriched gases, means for withdrawing the pitch, a heat interchanger, means for passing the enriched gases from the second still through the heat interchanger and for bringing them into indirect contact with one of the tars therein whereby the tar is preheated and the enriched gases are cooled, a vapor box for separating vapors from the undistilled portion of the preheated tar, a cooler for condensing said vapors, and a vacuum pump connected with the cooler.

14. In combination with a coke oven plant, a still having means for introducing hot coke oven gases thereto and for removing hot enriched-gases therefrom, means for introducing tar to the still, means within the still for bringing the tar into intimate contact with the gases in the still in the form of a fine intense spray to effect rapid distillation thereof and the production of a high melting point pitch, with means for withdrawing the pitch from the still, a second still, means for introducing the hot enriched gases from the rst still to the second still, means for introducing tar to the second still and bringing it into direct contact with the hot gases in the still to distill the tar and to produce a low melting point pitch, and means for removing the pitch from the still with means for bringing the resulting enriched gases into indirect contact with one of said tars.

15. In combination with a coke oven plant, a still having means lfor introducing hot coke oven gases thereto and forremoving hot enriched gases tion thereof and the .production of a high melting therefrom, means for introducing tar to the still, means within the still for bringing the tar into intimate contact with the gases in the still in the form of a fine intense spray to effect rapid distillapoint pitch, with means for withdrawing the pitch from the still, a second still, means for introducing the'hot enriched gases from the rst still to the4 second still, means for introducing tar to the second still and bringing 'it into direct contact with the hot gases in the still to distill the tar and to produce a-low melting point pitch, and means for removing the pitch from the still, and with means for bringing the resulting enriched gases in indirect contact with the tar being introduced into the second still whereby the tar is preheated and the gases are cooled and oils are separated therefrom.

16. In combination with a coke oven plant, a still having means for introducing hot coke oven gases thereto and for removing hot enriched gases therefrom, means for introducing tar to the still, means within the still for bringing the tar into intimate contact with the gases in the still in the form of a ne intense spray to effect rapid distillation thereof and) the production of a high melting point pitch, withmeans for withdrawing the pitch from the still, a second still, means for introducing the hot enriched gases from the rst still to the second still, means for introducing tar to the second still and bringing it into direct contact withthe hot gases in the still to distill the tar to produce a low melting point pitch, and means for removing the pitch from the still with means for bringing the resulting enriched gases in in" direct contact with the tar to be distilled in the second still whereby the tar is preheated and heavy oils are condensed from the gases, and a fractional condenser for further cooling the partially cooled gases to separate oil fractions therefrom.

17. A still, means for admitting highly heated gases thereto, a tar feed to the still, a reservoir in the still for a small body of the tar, a roll positioned horizontally in the still and adapted to dip to a slight extent into the tar in the reservoir, means for rotating4 the roll at a high speed, a pitch draw-01T, a packed tower througlr which the gases and vapors escape from the still, a tar feed to the packed tower, .and means for separately collecting from the bottom of the packed tower 125 residue from the distillation of tar in the tower.

18. In combination with a coal distillation plant, a still, means for conveying gases from the coal distilling means of the plant to the still, means for introducing tar to vthe still, mechanical agistating means within the still for bringing tar intoA intimate contact with the gases in the still in the form of a ne intense spray, a pitch draw-0E from the still, a second still, a main for conveying hot enriched gases from the rst still into the second still, means for introducing tar to the second still and bringing it into direct contact with.I hot gases therein whereby the tar is distilled and low melting point pitch is produced, a pitch draw-olf from the second still, a condenser, a main for conveying gases from the second still to the condenser.

. ARTHUR H. RADASCH.

' CERTIFICATE OF CORRECTION.

Patent No. 1,927,298. September 19, 1933.

ARTHUR H. RADAscH.'

It is hereby certified that error appears in the printed specification of the l above numbered patent requiring correction as follows: Page 3, line 75, for "intcnsve" read intense; and line 140, for "sepaartely" read separately; page 5, lines 119 and 149, claims 2 and 4, respectively, for "direct" read indirect; and that` the said Letters Patent should be'read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 14th day of November, A. D. 1933.

F. M. Hopkins (Seal) Acting Commissioner of Patents. 

